The 9th U.S. Circuit Court of Appeals says Arizona's law banning abortions after 20 weeks of pregnancy is unconstitutional, citing just about every Supreme Court case on the subject since Roe v. Wade.

"The 20-week law is [an] unconstitutional under an unbroken stream of Supreme Court authority, beginning with Roe and ending with Gonzales [v. Carhart]," the court says. "Arizona simply cannot proscribe a woman from choosing to obtain an abortion before the fetus is viable."

A federal judge had given the green light on the ban, as U.S. District Judge James Teilborg claimed that the state Legislature cited "substantial and well-documented evidence that an unborn child has the capacity to feel pain during an abortion by at least 20 weeks gestational age."

According to the appellate court ruling, everyone was in agreement that fetuses aren't viable at 20 weeks gestational age.

"The district court so recognized, declaring it undisputed that viability usually occurs between 23 and 24 weeks gestation," the court says. "Accordingly, Arizona's ban on abortion from 20 weeks necessarily prohibits pre-viability abortions."

The panel maintained that the Constitution doesn't allow states to ban abortion before the fetus is viable.

Although Governor Brewer signed the bill into law in April 2012, an emergency injunction had been preventing the law from going into effect.

"Lawmakers cannot impose their personal ideologies on the women of Arizona," said ACLU of Arizona legal director Dan Pochoda says in a statement. "This law endangered women's health and was knowingly passed by the Arizona Legislature despite clearly violating established constitutional requirements."

Not only is this decision a loss for Attorney General Tom Horne and Maricopa County Attorney Bill Montgomery, who were arguing in favor of the ban, but it might also put a damper on the day of anti-abortion fanatic Congressman Trent Franks, who's trying to pass a nationwide ban on abortions past 20 weeks of pregnancy.

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